The present invention relates to a roll for a papermaking machine having at least one strip element extending substantially in the axial direction of the roll, which is supported, substantially against radial forces, by a plurality of supporting elements.
A roll of this kind has been known from U.S. Pat. No. 4,584,059. The known arrangement is a shoe press roll where a press blanket is guided on guide strips that are supported by spring elements on an inner stiff carrying body so as to ensure a non-bending behavior of the press blanket in the axial direction. It has been found to be a disadvantage of this design that configuring the inner carrying body as a stiff element requires much input and is, thus, expensive especially in the case of press rolls of great width. In addition, when the carrying body bends, its studs assume an inclined position so that the carrying body moves away from the back-up roll at its ends, too. This, too, would result in an undesirable vertical displacement of the sliding surface of the strip element relative to the sliding surface of the press shoe, especially in the presence of high line loads or in the case of long studs. Further, one can also imagine applications where it is by no means desired to have a straight profile of the guide strips, but the aim is rather to adjust a predetermined bending curve of the guide strip in response to an outer load.
In the case of shoe press rolls according to the afore-mentioned U.S. Pat. No. 4,584,059, the press blanket revolves about a stationary carrying body, and if the press blanket revolves at a sufficiently high speed a hydrodynamic lubrication is said to be achieved. In certain cases, especially when no space is available for a felt guide roll on the infeed side of the shoe press, there is a risk that the felt, being under a certain tension in the longitudinal direction, may press the press blanket against the infeed area of the press shoe in such a way that under certain load conditions a hydrodynamic lubrication wedge cannot develop as required. This may lead to premature wear of the press blanket, due to insufficient lubrication. In addition, these conditions may result in considerable heating of the press blanket, increased power consumption and variations of the press parameters.